The present study proposes to use detailed health records to explore links between sharp-instrument injuries (SII) and exposure to blood and body fluids (BBFE) among health-care workers (HCWs), and HCWs personal use of clinical services. Such research will result in a more accurate assessment of the economic and health impacts of SII/BBFE incidents, as well as an estimation of the current systems in place to address the sequels of such incidents. By means of sophisticated electronic health information technology, detailed data will be obtained to explore the selection, design, and implementation of engineering systems, clinical protocols, and subsequent research efforts in the future. We will be using records from the Kaiser Permanente Northwest (KPNW) health-maintenance organization clinical services, so barriers to access to care, lack of standardization of clinical/laboratory data and data entry procedures, and other confounders will be controlled for in the research design. More stringent measures than the already high standards currently in place will be employed to maintain the anonymity and confidentiality of these records during the investigation. In the present study, (Specific Aim 1) we will undertake both a case-referent study and a pre-post study using electronic records of HCWs with a clinical position at KPNW to establish and characterize whether or not an association exists between SII/BBFE incidents reported, and the increased use of clinical services in the short and in the long term. We will also (Specific Aim 2) establish a classification of risk in terms of circumstances of SII/BBFE incidents by evaluating the relative contribution of the factors making up an employee profile (job description; mechanism of injury; purpose of offending device; and so on). The results from this exploratory investigation will identify research opportunities to fill some of the gaps outlined in the National Occupational Research Agenda (www.cdc.gov/niosh/nora). These opportunities will hopefully lead in the future to a more accurate body of knowledge for policy makers, clinicians, and health plan administrators to ensure that timely interventions to ameliorate the effect of health hazards may be planned and implemented for at-risk employees. This study will provide important information to establish the current impact of SII/BBFE incidents in HCWs, in terms of their utilization of clinical services and associated costs.